I'm going to be purchasing a solid state drive for my Macbook Pro and from everything I've read I should go with the Intel X25-m. I'm currently debating between the 80gb version and the 160gb version. I have all my large files on an external HD so the size of the 80gb version wouldn't be a problem, but I've read that you want to leave a lot of free space on an SSD. Is there any truth to this? I usually use around 50gb of hard drive space. I would obviously rather get the 80gb version cause $450 is a lot to spend on a hard drive, but if filling the 80gb version up is going to slow it down, kind of defeats the purpose of getting an SSD in the first place. I also transfer a lot of files between my laptop and my external drives. Does this degrade the performance of the SSD considerably? Any help is appreciated. Thanks